First of all: The whole "Love Can Wait"-movement is not the right answer. Why? Read on.
Teenage pregnancy isn't my problem, obviously. On one hand I can hardly become pregnant without a man (which means I'm pretty sure that I'm not pregnant right now), on the other hand I'm 32, so I can hardly be called a teenager any longer.
But even in Germany teenage pregnancy is a problem for society. It's not as much that there are additional children (as my post yesterday has pointed out, we direly need them), but that there are less adults who've finished school and learned a profession - mainly the girls who give birth to those children (as the teenage fathers rarely have to deal with suddenly having to take care of a child). And usually it's not the children of the higher classes who become pregnant during their teenage years - meaning those whose parents can afford to raise the child so their daughter can finish school and learn a profession. No, it's the girls from the lower social classes who have children while still being children themselves. And their parents hardly can raise the children they already have.
Especially in the United States (but in Europe, including Germany, as well) the churches (and especially the Roman-Catholic Church) advocate movements like "Love Can Wait" or others, basically telling the teenager that the best way not to become pregnant is not to have sex. While this surely is right, it doesn't help much with the problem as a such.
Lets say a girl becomes member of such a movement at the age of 12. She's more of a child than a teenager then. She'll grow older and older and sooner or later the teenage hormones will kick in. She will watch boys more closely (or girls, but lesbian love isn't a problem when it comes to pregnancy), start to giggle when one of them talks to her (cliché, I know) and find a boyfriend. Then what? She has never learned about preventing a pregnancy because she always thought she would wait until she's married - and then having children would be okay. Boys are chronically bad at the whole prevention-business, so it would be up to her to take care, as she will have to live with the consequences. But she doesn't know how. Sooner or late they will land in bed - and she runs the risk of becoming a teenage mother...
Yes, the best way to prevent a pregnancy is - and always will be - not having sex. But in case you have sex, you should know about the other ways (and both the pill and condoms are quite safe, even though in both cases 1 out of 1,000 women will get pregnant while using those means). In addition condoms protect both teenagers from sexual diseases. My mother - and my parents were both quite modern when it came to such topics - also told me that not having sex was the best way to prevent pregnancy, but in addition she told me about the other means and made sure I knew I could come to her if I wanted the pill or just some good advice. (Ever since AIDS was discovered, buying condoms in Germany has not been a big problem [and when my parents had just gotten married and didn't want children immediately, they bought them through a mail order sex shop].)
So what I advocate is teaching teenagers early enough about preventing pregnancy. Most of them will have sex before they get married (if they get married at all), so instead of pretending that it won't happen, we should make sure that they are prepared when it does.